Avicenna J Med Biotech arij002 Avicenna Journal of Medical Biotechnology 2008-2835 2008-4625 Avicenna Research Institute ajmb10363 Menstrual Blood-derived Stromal Stem Cells Augment CD4+ T Cells Proliferation AleahmadMehdiGhanavatinejadAlirezaBozorgmehrMahmoodDepartment of Pharmaceutical Biotechnology, Faculty of Pharmacy and Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, IranShokriMohammad-RezaNikooShohrehTavakoliMaryamResearch and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, IranKazemnejadSomaiehNanobiotechnology Research Center, Avicenna Research Institute , Tehran, IranImmunology Research Center, Faculty of Medicine, Iran University of Medical Sciences , Tehran, IranShokriFazelDepartment of Immunology, School of Public Health, Tehran University of Medical Sciences , Tehran, IranMonoclonal Antibody Research Center, Avecinna Research Center ACECR , Tehran, IranZarnaniAmir-HassanDepartment of Immunology, Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR , Tehran, Iran 10 3 183 191 2 1 2018 23 1 2018

<p>Background: It is more than sixty years that the concept of the fetal allograft and immunological paradox of pregnancy was proposed and in this context, several regulatory networks and mechanisms have been introduced so far. It is now generally recognized that mesenchymal stem cells exert potent immunoregulatory activity. In this study, for the first time, the potential impact of Menstrual blood Stem Cells (MenSCs), as surrogate for endometrial stem cells, on proliferative capacity of CD4+ T cells was tested.<br /> Methods: MenSCs and Bone marrow Mesenchymal Stem Cells (BMSCs) were isolated and assessed for their immunophenotypic features and multi-lineage differentiation capability. BMSCs and MenSCs with or without IFN&gamma; pre-stimulation were co-cultured with purified anti-CD3/CD28-activated CD4+ T cells and the extent of T cell proliferation at different MenSCs: T cell ratios were investigated by CSFE flow cytometry. IDO activity of both cell types was measured after stimulation with IFN&gamma; by a colorimetric assay.<br /> Results: MenSCs exhibited dual mesenchymal and embryonic markers and multi-lineage differentiation capacity. MenSCs significantly increased proliferation of CD4+ cells at ratios 1:2, 1:4 and 1:8. IFN&gamma; pre-treated BMSCs but not MenSCs significantly suppressed CD4+ T cells proliferation. Such proliferation promoting capacity of MenSCs was not correlated with IDO activity as these cells showed the high IDO activity following IFN&gamma; treatment.<br /> Conclusion: Although augmentation of T cell proliferation by MenSCs can be a basis for maintenance of endometrial homeostasis to cope with ascending infections, this may not fulfill the requirement for immunological tolerance to a semi-allogeneic fetus. However, more investigation is needed to examine whether or not the immunomodulatory properties of these cells are affected by endometrial microenvironment during pregnancy.</p>